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POPython comma separated print changes function behavior
 

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    <p>Although I've seen other questions on Python delimiters I haven't been able to find a question answering this so here goes. I'm writing a function that will recursively print an array backwards, and it appears to work just fine:</p> <pre><code>def print_array_backwards(array): if (len(array) == 1): print array[0], return print_array_backwards(array[1:]) print array[0], ########################################## x = [0, 1, 2, 3, 4, 0, 1, 2, 3, 4] print 'Array = ', x print_array_backwards(x) </code></pre> <p>Will output:</p> <pre><code>Array = [0, 1, 2, 3, 4, 0, 1, 2, 3, 4] 4 3 2 1 0 4 3 2 1 0 </code></pre> <p>The problem is when I try to print the output of the print_array_backwards function in line with other text, like this:</p> <pre><code>print 'Array = ', x print 'The array backwards is', print_array_backwards(x) </code></pre> <p>This will output:</p> <pre><code>Array = [0, 1, 2, 3, 4, 0, 1, 2, 3, 4] The array backwards is 4 3 2 1 0 4 3 2 1 0 None </code></pre> <p>My question is, where does this extra None value come from??</p> <p>If I push the function output to the next line but leave the comma with the print statement like this:</p> <pre><code>print 'Array = ', x print 'The array backwards is', print_array_backwards(x) </code></pre> <p>I obviously get the desired output:</p> <pre><code>Array = [0, 1, 2, 3, 4, 0, 1, 2, 3, 4] The array backwards is 4 3 2 1 0 4 3 2 1 0 </code></pre> <p>Can anyone help me understand why leaving the function in the same line of the print statement causes the function to behave differently? </p> <p>Thanks for your time!</p>
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